Superficially-finished rubber article or material and method of producing same



Aprll 7, 1925. 1,532,234

, C. H. DENNISON SUPERFICIALLY FINISHED RUBBER ARTICLE OR MATERIAL AND METHOD OF PRODUCING SAME Original Filed Aug. 27. 1921 avwentoz. Cimr/eslimwzkolz,

' applying a varnish to the surface, butif'this Patented Apr. 7, 1925 UNITED STATES PATENT OFFICE.

H. DENNISON, OF OUIN'CY, MASSACHUSETTS, ASSIGNOIB TO AMERICAN RUBBER COMPANY, OF EAST CAMBRIDGE, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

SUPERFICIALLY-FINISHED BUIBC BER ARTICLE OR. MATERIAL AND METHOD 01 PRO- DUOING SAME.

Gontinuationot application, Serial No. 496,008, filed August 27, 1921. This application filed December.

8, i822. Serial N0. 605,178.

To all whom it may concern:

Be it known that I, CHARLus H. DENNI- soN, a citizen of the United States, residing at Quincy, in the county of Norfolk and 5 State of Massachusetts, have invented certain new'and useful Improvements in Superficially Finished Rubber Articles or Materials and Methodsof Producing Same, of which the following is a full, clear, and exact description. p This invention relates to superficially finished rubberarticles or materials and the filed August 2 ,-1921. a

method of producing same, and more particularly to the production of such articles or materials with a hardened or frictionless surface or both, and is a continuation of m co-pending ap lication Serial No. 496,008,

. Articles or materials formed of uncured or soft cured rubber have a soft surface and the characteristic non-slip or frictional feel of rubbep, whereas, in the rubber art, it is often desirable that .such articles or materials have a hardened or frictionless surface,

viate the latter of these objections, in the case of water. bags, rubber footwear and other articles, by applying starch to thesurface prior to vulcanlzl'ng to produce the sotion no suitable method of producing a hard" surface when desired has been devised. Many rubber articles are also finished by :.,varnish is a hard one, intends to check or crack in use when applied.v to a flexible artie,

. cle, and at best is a mere makeshift. More:

over, in the use of such varnishes. whena'p'fi plied to relatively thin-walled articles,"-'the leather, but articles made 0.: such material have a soft and dull exterior surface entirely dissimilar-to. the relatively hard surface ofifinished leatheifj-and they -ar'e also 'or both. Attempts have been made to obsheet 6 then.

lacking in the leatherlike slip or feelto the touch characteristic of finished leather. Prior to my invention,

plied to such imitation leathers of vulcan-' the only finish ap lzable material has been varnish, which is Still another object is to provide an improved method for making imitation leather from vulcanizable .materlal.

of rubber having improved surface characteristics.

A-still further object is to produce a rubber-containing material or article with a leatherlike finish.

reference is had to the accompanying specification and drawings, which latter illustrate a and in which A further objectis to produce an articlespecific embodiment thereof,

F or a detailed: disclosure of the invention Figure 1 is a diagrammatic view illus I trating a calendar and a device for coating the calendered, sheet to thereof; and p Figure 2 is a diagrammatic view. of an apparatus used in prevent sticking in sheet mate- The invention will first bedescribed with reference to thespecific embodiment dis-' closed in the drawings, in which latter a backingsheet 1 (Fig, 1) is 'assedj 'between "the calender rolls 2 and 3 an coated with a vulcanizable compound 4 insertedJbetween the; calender rolls 3 and 5. The calendered passes overthe guide rolls 7 producing a hardened surface and leatherhke sli 'ria'lj such' as imitation leat er.

a a 0m 1 9 imme s in w ceptacle 10 containing soa solution. The excess solution is remove by the scraper 11, and the sheet after passing over the rolls 12 and 13 is wound up on the roll 14 with or without a liner from the roll 15. It is preferred to have the wind-up roll and liner roll in duplicate, as shown at 16 and 17. The sheeted material is then hung up on racks in a vulcanizer and cured. After ouring, a roll 18 of the material is di osed in the apparatus shown inFig. 2, and t e sheet 19 of the material is passed over the guide rolls 20, 21 and 22, a knife edge or spreader 23, preferably of glass, being disposed between the rolls 21 and 22. The numeral 24 designates a receptacle, which in the present instance, is used to hold a solution of bromine in carbon tetrachloride, and the solution is supplied by the manifold 25 to the spreader 23. From the roll 22 the coated sheet passes over a steam box 26 where the solvent is evaporated, and after passing over the roll 27 is wound up on the roll 28. As many treatments with thebromine solution are given as are necessary to produce the desired effect, and it has been found in practice that two ordinarily are sufiicient. The action of the bromine on the compound is such-"as to produce a superficial harden ing and removes the non-slip or frictional feel of the rubber, leaving instead a leatherlike slip which is a very close approximation of the feel of finished genuine leather.

trial, a surface la er or coating is need of an entirely di erent nature from the vulcanizable material directly next to it, with a distinct line of demarkation between the two. By no process, however, the vulcanizable material itself is hardened and otherwise changed at and immediately adjacent its surface, and the chan e extends inwardly a short distance in gra ually lessening degree, thus providing a hardened and wearresisting surface of great durability, is an integral part of the material and free fif'pm any tendency to check, crack or pool 0 The material produced b the, specific embodiment of the process a ove described is capable of various uses as a substitute for leather and is particularly adapted for use in the making of imitation leather or socalled leatherette coats. For certain purposes it may be desirable to incorporate in the vulcanizable compound a certain amount of round leather and in the manufacture of imitation leather containing this, the backing sheet is first friction coated with a rubber compound which contains no leather,

old then given a secondcoating on a calenier with a compound containing the ground leather, and the sheeted material is then given a coat of soap solution in a manner similar to that disclosed in Figure 1. It is By the use of varnish, or other coating mapro which preferred in this case to treat the sheet material with a bromine solution before ouring and the sheet is therefore next run through the apparatus disclosed in Fig. 2 as many times as is necessary to produce the desired result, after which the imitation leather may be embossed in any suitable grain, if desired and finally cured. However, the method last described may be vabest practice may dictate, and the invention,

includes spraying, dipping, brushing or any other suitable method'of applying the treating agent. The invention is capable of extensive use wherever it is desired to impart the surface characteristics of hardness and sli or either of them, to articles or materials of rubber, or its compounds, such as water-bottles, inner tubes, tires, rubber toys,

rubber tiling, etc.

It is preferred to use bromine in the superficial treatment of the'materia-l'as it is relatively inexpensive, and its action, wlylle sufliciently rapid, is readily controlled and not harsh, producing in the material that much to be desired smooth and non-frictional slip to the touch characteristic of the natural finished leather, and also superficially hardening it. However, it has been found that chlorine and iodine have a superficial action on the rubber and the scope of the invention includes the use of any suitable equivalent for the bromine. Carbon tetrachloride is preferred asa solvent owing to its volatility, non-inflammability, com parative cheapness', and chemical incrtness with respect to the materials employed, but any other suitable solvent'may be substituted. It has been found in practice that with the majority of compounds the strength of the solution may be in the proportion of about c. c. of bromine to 2500 c. c. of carbon tetrachloride, but the strength will, of course, be'varied, according to the length of time during which material is exposed to the action and also in accordance with the material used and the depth and degree to which the change in character is desired. In practice when the material is to be cured the use of the ordinary dry heat cure in vulcanizing has been found to be very satisfactory, but the steam cure may also be used,

' and in certain conditions may perhaps be preferable, or a combination of both dry heat and steam cure may be employed. The soap solution is used to prevent sticking of the sheeted material, and in the case where the calendered material is to be supplied directly to the bromine spreading apparatus or the material is not in sheet form, the use of the soap solution may be dispensed with.

It will be seen that by my invention, rub-. ber articles and materials generally maybe provided with a hard and frictionless sur face which will not check, crack or peel off, and which forms an integral part of the material itself, and the invention is capable of extensive application in the rubber art.

It is obvious that with the above disclosure numerous modifications will suggest themselves to those skilled in the art, and it is not desired that the invention be limited other than by the scope of the appended claims.

Having thus described my invention, what I claim and desire to protect by Letters Patent is z 1. The method of changing the surface characteristics of a rubber containing material which consists in superficially hardening it by treatment with bromine.

2. The method of changing the surface characteristics of a rubber containing. ma terial which consists in applying a free halogen in dilute solution to the surface of the material. v

3. The method of changing the surface characteristics of a rubber containing material which consists in applying bromine in solution to the surface of the material and removing the solvent by heat.

' 4. The method of changing the surface characteristics of a body of, rubber or a compound thereof which consists in hardening and imparting a leatherlike slip or gloss to the surface of the body by a brief treatmont of the surface with a dilute solution of bromine.

The method of producing a superficial hardening and leatherlike slip or gloss on rubber or compounds thereof which consists in both superficially treating it with a halogen and vulcanizing it.

6. The method of producing a superficial hardening and lcatherlike slip or gloss on rubber or compounds thereof which consists in both superficially treating it with bromine and vuloanizing it.

7. The method of producing a; superficial hardening and 'leatherlike slip or gloss on rubber or compounds thereof which consists in both superficially treating it with bromine in solution and vuleanizing.

8. The method of making an imitation leather which. consists in sheetin a vulcan izable compound, hardening t e surface thereof and imparting a leatherlike slip or gloss to it by one or more applications of a halogen to the surface, and finally curing.

9. The method of making an imitation leather which consists in coating a fabric with a vulcanizable compound, superficially treating the compound with a halogen, and.

finally curin p 10. The method of making an imitation leather which consists in coating. a fabric with a vulcanizable compound, applying a .plurality of coatings of a halogen 1n solution and drying between the coatings, and finally curing. I

11. The method of making an imitation leather which consists in coating a fabric with a vuleanizable compound, applying a plurality of coatings of bromine in solution and drying between the coatings, and finally curing.

12. The method of making an imitation leather which consists in coating a fabric with a vulcanizable compound, superposing on saidcoating a coating of a vulcanizable compound containing leather, superficially treating the material with a halogen, and curing by heat.

13. The method of making an imitation leather which consists in coating afabric with a vulcanizable compound, superposing on said coating a coating of a vu eanizable compound containing leather, superficially treating the material with bromine, whereby a leather-like slip or gloss and surface hardening is produced, and curing by heat.

14. The method of making an imitation leather which consists in coating a fabric with a vulcanizable compound, superposing on said coating a coating of a vulcanizable compound containing leather, superficially treating the material one or more times with a solution of bromine, -whereby a lea-therlike slip or gloss and surface hardening is produced, and curing by heat.

15. The method of making an imitation leather which consists in coating a fabric with a vulcanizable compound, calendering on said first coating a coatingv of a vulcan izable compound containing leather, applyinga coating of soap solution, applying one or more coats of a solution of bromine in carbon tctrachlmide and drying between coats, suitably embossing, and curing by heat.

16. As a new article of manufacture, a body formed of vulcanized rubber or a compound thereof and having an integral bnomine terial and leather and having an integral body having ahardencd and frictionless surbromine hardened surface portion characface portion of a rubber containing material 10 1 terized by a frictionless leatherlike slip or combined with bromine.

feel to the touch. Signed at Cambridge, county of Middle- 5 19. As a new article of manufacture, a sex, and State of Massachusetts, this 29th body having a bromine-hardened rubber day of November, 1922.

containing surface portion.

20. As a new article of manufacture, a CHARLES H. DENNISON. 

